Reineorced-coircilete ship and method oe constructing same



R. R. LEFFLER. REINFORCED CONCRETE SHIP AND METHOD 0F CONSTRUCTING SAME.

APPLICATION FILED MAI/s1. ma. 1,305,379. Patented June 3,1919.

2 SHEETS-SHEET I.

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H. R. LEFFLER; REINFORCED CONCRETE SHIP AND METHOD 0F CONSTRUGTING SAME.

APPLICATION FILED MAYSI. |918. 1,305,379.

Patented June 3, 1919.

2 SHEETS-SHEET 2 IIIII. F r L I I I I T I II UNITED STATES PATENTCFFICE. f

RALPH It. LEFFLER, OF CHICAGO, ILLINOIS.

nnrNroncED-concnn'rn sHIP ANDY METHOD or consrnuc'rmc SAME.

Application filed May 31, 1918.

ToV all whom t may concern Be it known that I, RALPH R. LnrFLnR, acitizen of the United States, residing at Chicago, in the county of Cookand State of Illinois, have invented certain new and useful Improvementsin Reinforced-Concrete Ships and Methods of Constructing Same, of whichthe following is a specification.

This invention relates to reinforced con 7 crete construction and moreparticularlyk to such construction as applied in the building of ships.

During the present great demand for ships many concrete ships are beingbuilt and many more will be planned for the future.` If these concreteships are to be a commercial success after the war it is almost.

essential that their hull weightI shall not substantially exceed that ofsteel ships; and to make possible this result and at the same doubleconcrete shell requiring no planking or the like; further theconstruction of the bottom of a ship after the manner of a doublediagonal concrete Pratt truss; further to extend the beams or theverticals of the truss almost the length of the ship thus carrying anylocal inequality of loading a greater distance longitudinally than inthe old type employing transverse framing; further to form the diagonalsof the Pratt truss of metal rods or bolts; further to also form thesides of the hull of Pratt truss construction extending either the fullheight or any` fractional distance desired; further to provide verticalbeams to extend over that portion' of the sides vwhich may not be cov?ered by the Pratt truss construction; further to provide steel plates onthe inside of .the concrete vertical beams to carry longitu-Speciflcation of Letters Patent.

Patented June 3, 1919.

serial No. 237,534.

dinal shear and serve as an inner wall or shell; further to provideangle bars to transmit the stress from the metal diagonals t0 theconnecting truss members and at same time serve as longitudinalreinforcement of the ship; further to notch the angle bars to permitvthe reinforcing bars of the chords to drop into the legs of the anglebars; further to notch the top portion of the truss verticale orintercostals to'effect amore efficient connecting vof the adjacentconcrete fillet and also l'ofthe intercostal with the upperand lowershell portions or floor; further to irmly secure the diagonals of thePratt truss construction to the respective arms of the angle bars; andsuch further objects, advantages and capabilities as will later morefully appear. l Y

.My invention further resides in the combination, construction andarrangement of parts illustrated in the accompanying drawings, and whileI have sho-wn therein a preferred embodiment I desire the same to beconsidered as illustrative only and notas limiting the scope of myinvention.

Referring to the drawings:

Figure l is a transverse vertical section illustrating my invention asembodied in a ship, one half being omitted for the reason that the twohalves are symmetrical.

Fig. 2 is a fragmentary plan view of 'a portion of the floor showing thearrangement of the reinforcing and angle bars.

Fig. 3 is a fragmentary vertical section through the upper portion ofthe floor.

Fig. l is a plan view of a portion of one of the truss verticale orintercostals. n

Fig. 5 is a section on the line 5 of Fig. 3.

Fig. 6 is a section on the line V6 of Fig. but omitting all parts exceptthe truss verticalsand the angle bars for the sake of clearness inshowing thisconstruction.

Fig. 7 VVis a fragmentary longitudinal transverse section on the line 7of Fig. l.`

Fig. 8 is a side elevation of Fig. 6. y

Fig. 9 is a vertical transverse section through one of the trussverticalevv or interlcostals and showing the angle bars in positionratthe top and bottom edges thereof.

In the drawings I have illustrated my in-k ventionas embodied in theconstruction o-f ships,and referring to Fig. l, it will be seenV thatsuch ship comprises the bottom l; sides 5 and bilge block 6. As will beseen, the bottoni is of double diagonal conc-rete Pratt trussconstruction, which truss construction may also extend a suitabledistance up the sides of the hull, which distance have illustrated inthe drawing as reaching to the neutral axis of the ship; however, it isobvious that if desired this Pratt truss construction may be extended upthe side of the hull entirely to the main deck, or a fractional portionof such distance if'desired.

In Fig. 1 the construction of the sides of the hull lying between theupper end of the truss construction and the main deck comprises thesingle outer shell 7, (which of course will be suitably reinforced), andthe vertical bea-ms 4 on the inner edges of which are secured the steelplates 8 suitably riveted together and anchored at their upper and loweredges in the concrete as shown.

Referring to Fig. 7, it will beseen that I have provided the verticallyextending angle plates 9, which are suitably secured to the steel platesS, and through the other leg of which extends the bolts 10 into theconcrete of the ribs 4. Also bolts or projections 111 are providedextending from the plates 8 into the concrete of the rib 4. Thisconstruction will secure the plates 8 in a firm manner to the ribs 4.These plates 8 serve the double purpose of carrying the longitudinalshear and also serving as an inner wall or shell.

By providing the braces 3 and I beams 28 the length of the bottom trusswill be divided up into substantially three equal portions, and insteadof having, say for example, in a ship of 45 foot beam, a truss spanning45 feet there will be three trusses each spanning approXiniately 15feet, thus shortening the spans and decreasing the magnitude of thestresses Caused. The cross braces will be suitably secured by means of Ibeams 10 to the ribs 4, and to the sides of the hull.

Turning now to the details of the double diagonal concrete Pratt trussconstruction, and referring` to Figs. 2 to 9, it will be seen that Ihave provided the truss verticale` or intercostals 11, which areprecast; that is molded and hardened prior to the construe-` tion of theship bottom and sides. These iiiteicostals or truss verticals areprovided at suitable distances with the outwardly eX tending ribs orwings 12 to give the necessary .rigidity and strength. As will be seenin Figs. 6 and 9, the longitudinal edges of the intercostals are formedwith V-shaped grooves, in which V-shaped grooves are inserted the angleIbars 13, which bars, while shown as forming an angle of 90", may be ofany other desired angularity, the essential feature beiii-g that therespective arms of these bars occupy a position at substantially rightangles to the diagonal rods 14, see

Fig. 5. The intercostals 11 are notched or recessed at their upper andlower edges as indicated at 15, the ends of whichnotches or recessesmay, if desired, be of dove tail formation, as indicated at 16 wherebyto securely imite the concrete of the fillet thereto. Near the ends ofthe notches 15 and embedded in lthe intercostals 11 are the staples 17,which extend into the recesses 15 a suitable distance to receive andpermit to extend therethrough the rods 18, which as shown in Fig. 5extend from the upper portion 19 of the bottom down through the fillet20, and up on the other Side of the intercostals again entering theupper portion 19, thus firmly reinforcing and securing together theconcrete of the yLipper portion 19, the fillets 20, and theintercostals.

Extending longitudinally through the fillets 2O are the reinforcing bars21, whichl may be square or of any other suitable cross section. Restingupon the upper surfaces of these bars 21 are the transverse reinforcingbars 22, which bars will be noted are located below the neutral axis ofthe upper portion 19 of the truss construction. The angle bars 13, aswill be seen in Fig. 8, are provided with the notches 23, the functionof which is to permit the transverse rods 22 to be seated therein, thusaccommodating these bars to the desired height, and rendering possiblethe securing of a. minimum of thickness for this shell construction. Asseen in Fig. 6, the slots 23 are formed by providing suitable slits inthe sides of the metal and bending the portion 23 outwardly. Alsoextending transversely of the upper portion 19 of the floor are thesmaller reinforcing rods 24, which may during the process of placing theconcrete be held at the appropriate height by placing other rods betweenthese rods and the upper surface of the rods 22, or any otherappropriate manner.

Referring to Fig. 5, it will-be seen that the diagonal rods 14,extending through the angle bars 13 are provided' with nuts 25, whichwhen vassembling the parts may be suitably tightened to secure thediagonals 14 to the angle bars 13. It will also be noted that the endsof the diagonals 14 at a little distance beyond where they pass throughthe angle bars 13 are bent downwardly, as indicated 26 to lie in a planeof the floor 19, thus providing further reinforcement in this region. Itis to be understood that the details of construction at the juncture ofthe bottoms of the intercostals 11 and the outer shell 27 are the sameas those described above for the upper shell 19; the diagonals 14passing from oneedge of one of the upper angle bars 13 to a diagonallyopposite lower bar 13, as clearly seen in Fig. 1. The lower end of thebrace 3 is suitably secured to the I beam 28 incorporated in the bottomof the vessel.

The Pratt truss construction will be extended to the sides of thebottom, at which point they will merge into the bilge block 6, in whichbilge block is suitably located appropriate reinforcing means togetherwith the lower yedge of the steel plates 8, as clearly shown in Fig. l.lAs stated abo-ve, the double diagonal Pratt truss construction will becontinued upwardly from the upper portion of the bilge block to thedesired height.

The method of construction of my improved structure is as follows:

The truss verticals or intercostals 11 are first formed and hardened.All bars and reinforcing elements are then placed in an appropriatemanner in the exterior or outer shell of the bottom and also in both theexterior and interior shells of the sides. The preformed truss verticalsor intercostals are next placed inposition, and the metal diagonal rodsor bolts 14 are then placed and the nuts 25 suitably tightened to givethe necessary rigidity. The exterior bottom shell is then poured, whichIpouring is continued until the bilge blocks at each side of the bottomare reached, which -bilge block is then formed and the pouring continueduntil both the exterior and interior shells of the sides as far up asthe Pratt truss construction is extended are completed. It is herepointed out that in the formation of the Pratt truss construction in thesides that suitable metal of the hy-rib type will be placedto form theinner sides of the exterior and interior shells, it of course beingunderstood that suitable molds will be provided for the exterior of theouter shell of the side, while the steel plates 8 will form the mold forthat side of the inner shell toward the inside of the hull. The sides ofthe hull being completed, the reinforcing bars are then placed in theinterior shell portion V19 of the. bottom, hy-rib metal havingpreviously beeninserted and secured in place to form the underneath sideof thisv upper shell 19, which hy-rib metal will be of appropriate shapeto yform the fillets 20, which fillets as pointed out above extendthrough and are anchored in the recesses 15. While 1 have mentionedhy-rib, it is of course understood that any other suitable form of metallath may be used in this connection. The upper shell 19 of the bottom isthen poured and completed.

VBy thus making use of the'double diagonal Pratt truss construction informing the bottoms and sides or portions of the sides of concreteships, it will be seen that 1 have greatly reduced the weight of suchvessels while at the same time preserving the necessary strength. Byusing double diagonals in the Pratt truss construction, there isprovided at Vall times a. rod to carry the tension which may be set upin either of these diagonals, due to a reversal of stresses in the shipcaused by the different positions at which the vessel rides on thewaves. If desired an additional nut similar to the nut 25 may beprovided on the-oppositeVV side of the angle bar 13 and the diagonals1-1' thus enabled to carry a certain amount of compression, should thesame be necessary. This construction results in the elimination of theheretofore-used and massive transverse framing, and thus not onlyreduces the weight ofthe vessel to a considerable extent, but as-avresult ofthe double diagonal Pratt truss construction the stresseswill be much more evenly divided over the ship vand successfully takencare of in a manner quite similar to that accompanying' the use ofmushroom construction inthe erection of ioors and ceilings inreinforcedr concrete buildings. While the main function of the anglebars 13 is toV carry the longitudinal stresses caused by the movement ofthe ship when acting as a beam, or as a truss, it is pointed out thatthe incidental function of forming anchors for the diagr nal rods 14 isconsidered as nearly, .if'not fully, as important. These angle irons areY arrangedin staggered' relation with respect to the` jointsof the trussverticals or intercostals, so as to overlap these joints. The nuts onthe diagonal rods 14 are tightened prior to pouring the exterior shelland again prior to pouring the interior shell whereby to insure thenecessary rigidity in these parts.

Ifsome designer should prefer not to use the lsteel plates 8 thisconstruction could be modified so as to provide a lattice 4truss as asubstitute thereof either in the exteriorV or interior shell. v y

In constructing the Pratt truss in the sides ofthe hull the outstandingleg of the ver-4 tically extending angle plates 9 can be notched tosupport the inner ends of the truss verticals or intercostals in theVsides, and may have holes punched therein throughV which the round rodsreferred tol above can` `be inserted to furtherbindthe concrete and theangle web.' The thickness of the sides of the ship can be increased ordecreased as desired without markedlyV affecting thek weightV of thehull. i

Concrete vessels built after the type of the well known concrete vshipFaith will weigh from fifteen to twenty-'five per cent.

the use of any intermediate columns whatever, thus permitting themaximum of daylight to enter due to the absence of obstructing columns,and in such a construction the entire floor could be considered as alarge concrete truss slab. In a wider building having columns the trussslab could be considered the entire portion extending between columns orsupports; while in the form of ship illustrated in Fig. l the respectivetruss slabs would be those portions of the floor (including bothinterior and exterior s hells and the intercostals) lying betweensupports, that is between the respective I-beains 28, and between theseI-beams and the bilge blocks; also that portion of the sides above thebilge block. These portions could each be considered alone as a largetruss slab.

Having now described my invention I claim:

1. In a reinforced concrete ship, a hull having sides and a bottoni, thebottom comprising spaced apart reinforced concrete shells, concreteintercostals connecting said shells and double diagonals of metal rodsconnecting the diagonally opposite edges of said intercostals wherebysaid bottom will be of double diagonal Pratt truss construction toaccommodate all possible stresses set upV therein.

2. In a reinforced concrete ship, a hull having sides and a bottom, thebottom comprising spaced apart reinforced concrete shells, concreteintercostals connecting said shells, and double diagonals of metal rodsconnecting the diagonally opposite edges of said intercostals wherebysaid bottom will be of double diagonal Pratt truss construction toaccommodate all possible stresses set up therein, said double diagonalPratt truss construction also extending partially up the sides.

3. In a reinforced concrete ship, a hull comprising a side having aportion of its height of double shell formation, concrete intercostalsconnecting said shells, double diagonals of metal rods connecting thediagonally opposite edges of said intercostals whereby this portion ofthe side will be of double diagonal Pratt truss construction, said sidefor the remainder of its height being of single concrete shellconstruction with vertical beams.

et. In a reinforced concrete ship, a hull comprising a bottom of hollowdouble shell reinforced concrete construction having concrete verticals,and double diagonals of metal rods connecting the diagonally oppositeedges of said verticals.

5. In a reinforced concrete ship a double shell of double diagonal Prattconcrete truss construction and comprising truss verticals each havingan angle bar on its upper and lower edges, metal rod diagonals extendingfrom the upper edge of the verticals to the lower edge kof the adjacentvertical, said diagonals being secured to said angle bars.

G. In a reinforced concrete ship, a hull having a double shell of doublediagonal Pratt truss construction comprising truss verticals orintercostals, diagonals of metal rods extending between said verticals,and

angle bars to which said diagonals are se-v cured, said angle barscarried by the edges of said verticals and serving as anchors for saiddiagonals and at the same time as lonvgitudinal reinforcement of theship.

7. In a reinforced concrete ship, a hull having a double shell bottom ofdouble diagonal Pratt truss construction comprising concrete trussverticals, angle bars along the edges thereof, and diagonal rodsconnecting said angle bars, the upper and lower edges of said verticalsbeing recessed to accom modate fillets, fillets in the recesses, saidfillets being integral with the shell portions and acting therewith toembrace said angle bars.

8. In a reinforced concrete ship, a hull having a double shell of doublediagonal Pratt truss construction comprising truss verticals, an anglebar on each of said verticals, diagonal rods rigidly connecting saidangle bars, reinforcing rods, and said angle bars each having notches toreceive said reinforcing rods.

9. In a reinforced concrete ship, a hull having a double shell of doublediagonal truss construction comprising truss verticals, angle bars onthe upper and lower edges respectively of said verticals, and rodsconnecting the diagonally opposite angle bars, said rods passing throughand secured to said kbars and extending therebeyond for a substantialdistance in the plane of the shell member.

10. The construction of reinforced concrete ships having double shellsof double diagonal Pratt truss construction which consists in providingpreformed intercostals, laying the reinforcement including longitudinalangle bars of the outer shell, placing the intercostals in position onsaid angle bars, placing angle bars on the upper edge of saidintercostals, connecting the alternate upper and lower angle bars bydiagonal rods, tightening said rods, pouring the outer shell, placingmetal lath to form the lower surface of the interior shell, placing thereinforcenient thereon and pouring the interior shell.

11. lIlhe construction of reinforced concrete ships having double shellsof double diagonal Pratt truss construction which consists in arrangingthe reinforcement of the exterior shell including longitudinal anglebars, placing precast intercostals thereon, placing similar butreversely positioned angle bars alo-ng the opposite edge of saidintercostal, connecting said intercostals by diagonal rods, arrangingthe reinforcing rods rods connecting the alternate upper and of theinterior shell, and pouring the conloWer angle hars, interior andexterior shells, 15

crete of said shells. and llets connecting said intercostals and 12. Indouble diagonal co-ncrete Pratt said shells, said fillets extendingthrough truss ship construction, a plurality of interand on both sidesof said I'GCBSSGS- costals having recesses in their upper and In Witnesswhereof, I hereunto subscribe loWer edges, angle bars on the upper andmy 1121116 t0 this SpeCCatOIl.

lower sides of said intercostals, diagonal RALPH'R. LEFFLER.

Copies of this patent may 'ne obtained for five cents each, byaddressing the Commissioner of Patents, Washington, D. C.

